Cylinder lock key retainer and positioner



y 1949- G. E. SWANSON 2,469,018

CYLINDER LOCK KEY RETAINER AND POSITIONER Filed Aug. 17, 1945 5 if v" INVENTOR. W

Patented May 3, 1949 'GYLINDER-TLQCK KEYE'BETAINER D 1 PO SITIONER Gunnar E; Swanson, New Britai lQqnn.

ApplicationAug-usttfi, 1945, Serial No.:-.611;Q39

-6.Claims.

This. invention relatesto means for prevfi lting the-1 removal of:a key from -a cylinder. lock until thecylinder is turned to-such position thatthe key can befreely .pulled 'out Without liability of straining or damaging the tumblers. And it is particularlyaardapted'rfor locks that have unitspring tumblers or disk tumblers that are liable to beinjured if anattempt is made to pull out the: key .with thecylinder in awrong. position. The means to which: the invention. relates furtherserves :to indicate; to the user when the cylinderghas been'tunned toithe proper position o1nkey.-.withdrawa1.

.Thew-presentrinventiom contemplates providing the.;,correct;;ley-=with;1a; notch in. its vbitted edge or: in,- its,-,b.ack; edge; or; side; tproviding; the inner wallbf; the, barrel. with one; or more; recesses and pr vi ing; the: cylinder :near. one. end with a: slot in which 515:. a'.:pin/.ori;-p1ate that. is adapted to, be

cylinder isinrthe-wrong position for key withdrawal. and: moved; out ofg-the; notch-and into. .a recess .Whenethe. cylinder. iszturnedyto. .a :position which will; allow: the .free withdrawal. of, i the; key. 10st; the-accompanying adrawingsyfiig. J 1 shows a --portion; of; admit-spring tumbler.

Fig. -2. is a longitudinal; section -.of a unit-spring tumbler lock ,onuthe; dottedxline' 21-1-2 .ofhEigA, thistviewashowing the cylinder in position for lockingvand showing thakey: free for-withdrawal.

:-Fig. =3 isai transverse sectionon the dotted line 3+3 oi -Fig: "2 v Fig;: 4' is a transverse section'on the "dotted line 4-4- -n- Fig. 2.

5 isa longitudinal sectionon the dotted line 5-5of"F ig."6, this-view-being'similar to Fig. Z but showing the cylinder out of position for locking and showing the key held to prevent withdrawal.

Fig. 6 ,is a transverse section similar to'iig S but with 'thegparts in the relative positions shown in Fig.'5, this view being on the dotted 1ine .6 6'

.2 filed June 16, 1945 now Patent. No. 2 4(i,0, 551, a e E b u rmr. 19%? .Thebarrel Ill, has la longitudinal slot me into which the locking bar; l3.is.moved,.to effect. lockingsand fromtwl'iichgit is withdrawnto .effect .unlocking. The-bar [3 is biased for movement-in the inward or unlocking direction. Thebar is permitted to move -inward. for unlocking when thenotches 12 on-the. several spring. tumblers, l2 are brought into alignment; Thesaid notches are aligned when 7 the tumblers are-.engagedandflexed, as shown -in-Fi g s. 2 and l, by a-correctly bitted key 13 ;i ns erted in;the. keyvslot. Upon withdrawal of the vkey l3 the spring tumblers return to; their unflexedpositionsand the bar 13. is forced into the slot: .10 to, .efiectlocking. The said bar ltand the unit spring; tumblers l2 collectively constitute. the locking means on the cylinder.

''When the cylinder is ,out oflocking position. as shown in :Figs; 2,3; andg i as. for instance. .in the position shown in Eigs. 5 z and .6, the spring tumblers l2 arezrpreyentedaby. the bar 13 from flexing, and. the said tumblers are therefore. held in engagement lwith the keyso; as to, prevent, .or at. leastfltend to prevent, withdrawal-thereof. However,- thespring tumblers, when held against flexing,- .oifer. but; limited, resistance tokey withdrawal, and they;' would be buckIedor distorted with-resultant damagev if the key were forcibly withdrawn with the; cylinclenin other than locking osition, as forinstance in the position shown in;-Figs. 5 andg6. '-I he, parts .tofibe now described positively hold the key to prevent any possible withdrawal thereof,.- except .when; the cylinder is iniilocking position. as shown; inFigs. 2, 3 and 4.

In carrying out the invention asv herein illustrated thekey l3.*;has;.a notch; M ;in its bitted edge, the interior Wallpf'thebarrel has a concave recess l5, and the cylinder near its front end has a; slot l6 that-is thinner at its-. inner end thanat; its outer. end. 51118 11111?! edge .pf-- the notch M tint the; key provides a; shoulder which serves as hereinafter described to retain the key in places, except when thecylinderisin its locking position. Preferably ,the said; shoulder is. inclined; or; bevelled; as-sl'iown. The. key retaining means comprises a plate I! having a rounded outer end I8 and a perforation 19 (Fig. 8) loosely fitted in. the; cylinder, slot, and a spring 20set in the plate perzforation with oneend engagedwith theplate; and its other end engaged with the bottom pf thewidesth pz art of thecylinder slotand ftensioned. to normally press the. plate outward. (-F;ig.;; 2)

The barrel recess I5 and the key slot are so related that, when the cylinder is turned to the locking position in which the key can be freely withdrawn without straining the tumblers I2, the retaining plate I! is moved by the spring 20 into the barrel recess I5 and out of the key notch I4 so as to free the key for withdrawal (Figs. 2 and 3). In fact, when the cylinder has been turned approximately to the locking position as shown in Fig. 3, the spring biased plate I! serves by engagement with one inclined wall of the recess I5 to additionally turn the cylinder to the exact locking position. The plate II also tends by reason of the spring 20 to resist turning of the cylinder out of its locking position. The cylinder can be turned out of the said locking position, as for instance to the position shown in Fig. 6, only by applying sufficient force to overcome the action of the spring I! and to cam the plate I l inward by engagement with one inclined wall of the recess l5.

When the cylinder is turned out of the locking position shown in Fig. 3, the retaining plate I1 is forced inward by contact with one inclined wall of the recess I5 so that its inner end projects into the key notch [4. Thus any attempted withdrawal of the key I3 will be resisted solely by the plate I! and the key cannot bend or distort the tumblers I2. It will be clear that the cylinder can be turned in either direction from the locking position shown in Fig. 3 and that the key retaining action of the plate I? ill be the same irrespective of the direction of turning.

From the foregoing description it will be apparent that the retaining plate I! and the spring 20 serves in conjunction with the barrel recess l5 and the key notch I4 to accomplish several results. The plate I1 and the spring 20 not only serve to finally bias the cylinder to its looking position and to retain it therein, but they also serve to indicate to the user that the cylinder has been turned to its locking position so that the key can be readily withdrawn. When the cylinder is rotated the user can readily feel the entry of the member I! into the recess I5 and can feel the resultant increased resistance to rotation. This indicates that the cylinder is in looking position and that the key can be withdrawn. Without this means for indicating, the user would be unable to readily ascertain whether the cylinder had been moved to locking position and could determine the locking position only by the trial and error method of repeatedly attempting to withdraw the key in diiferent positions. Furthermore, the retaining plate I1, when forced inward as the result of turning the cylinder out of locking position, enters the key notch I4 to positively prevent key withdrawal. This is very important when the tumblers of the lock are small and delicate so that they would be damaged by a forcible withdrawal or attempted withdrawal of the key with the cylinder out of looking position. The spring tumblers I2 constitute an example of tumblers which would be damaged under the conditions stated.

The barrel It may, if desired, have a supplemental shallow recess 2| by means of which the cylinder may be located in a predetermined unlocking position as shown in Fig. '7. The plate l is moved into the recess 2| by the spring 20, but the recess is relatively shallow and does not permit the plate to be moved far enough to release the key. The supplemental recess 2| in conjunction with the spring 2|] and the member I! serves to indicate to the user that the barrel has been turned to a predetermined position other than the locking position and also serves to resist turning of the cylinder out of the said predetermined position.

The invention claimed is:

1. A cylinder lock comprising in combination, a barrel having a longitudinal locking slot, a rotatable cylinder in the barrel provided with a longitudinal key slot and provided with looking means which projects into the barrel slot to prevent cylinder rotation and thereby effect locking and which upon insertion of a correctly bitted key is withdrawn from the said slot to permit cylinder rotation and thereby efiect unlocking, a movable member carried by the cylinder and adapted to enter a notch in the key to prevent key withdrawal, means on the barrel which permits the said movable member to be moved out of the key notch when the cylinder is in looking position and which causes the said member to move into the key notch when the cylinder is turned out of locking position, and a spring which biases the said movable member for movement out of the key notch so as to permit key withdrawal when the cylinder is in looking position, the said spring in conjunction with the said movable member serving to indicate to the user that the cylinder has been turned to locking position and also serving to resist turning of the cylinder out of locking position.

2. A cylinder lock comprising in combination, a barrel having in its inner wall a longitudinal locking slot and a recess with lateral inclined sides, a rotatable cylinder in the barrel provided with a longitudinal key slot and provided with locking means which projects into the barrel slot to prevent cylinder rotation and thereby efiect locking and which upon insertion of a correctly bitted key is withdrawn from the said slot to permit cylinder rotation and thereby effect unlocking, a movable member carried by the cylinder and so located that it can enter the recess in in the barrel wall when the cylinder is in locking position, the said member upon rotation of the cylinder from locking position being movable inwardly out of the barrel recess by the inclined sides thereof to an inner position in which it is adapted to enter a notch in the key to prevent key withdrawal, and a spring which biases the said movable member for outward movement into the barrel recess and out of the key notch so as to permit key withdrawal when the cylinder is in looking position, the said spring in conjunction with the said movable member and the said barrel recess serving to indicate to the user that the cylinder has been turned to locking position and also serving to resist turning of the cylinder out of locking position.

3. A cylinder look as set forth in claim 2, wherein the cylinder is turnable in either direction from and to its locking position, and wherein the spring in conjunction with the movable member and the barrel recess serves upon turning of the cylinder in either direction to indicate to the user that the locking position has been reached.

4. A cylinder lock as set forth in claim 2, wherein the cylinder has in its inner wall a second recess shallower than the first said recess and so positioned that the said movable member can enter it when the cylinder is in a predetermined position other than the locking position, the second recess being of such depth that the movable member is prevented from moving outward sufiiciently to permit key withdrawal and the said second recess in conjunction with the said movable member and the said spring serving to indicate to the user that the barrel has been turned to the said predetermined position and also serving to resist turning of the cylinder out of the said predetermined position,

5. A cylinder lock comprising in combination, a barrel having a longitudinal locking slot,-a rotatable cylinder in the barrel provided with a longitudinal key slot, locking means on the cylinder comprising an element adapted to enter the barrel slot and comprising tumblers which upon engagement by a properly bitted key permit the said element to move inward from the barrel slot to permit cylinder rotation and thereby effect unlocking and which upon Withdrawal of the key cause the element to move outward into the barrel slot to prevent cylinder rotation and thereby effect locking, the said tumblers when the locking means is in unlocking position serving by reason of their engagement with the key to resist key withdrawal, a movable member carried by the cylinder and adapted to enter a notch in the key to prevent key withdrawal and to thereby avoid strains upon the tumblers due to attempted withdrawal of the key, means on the barrel which permits the said movable member to be moved out of the key notch when the cylinder is in locking position and which causes the said member to move into the key notch when the cylinder is turned out of locking position, and a spring which biases the said movable member for outward movement into the barrel recess and out of the key notch so as to permit key withdrawal when the cylinder is in locking position, the said spring in conjunction with the said movable member serving to indicate to the user that the cylinder has been turned to locking position and also serving to resist turning of the cylinder out of locking position.

6. A cylinder lock comprising in combination, a barrel having in its inner wall a longitudinal locking slot and a recess with lateral inclined sides, a rotatable cylinder in the barrel provided 6 with a longitudinal key slot, locking means on the cylinder comprising a locking bar adapted to enter the barrel slot and comprising spring tumblers which upon engagement by a properly bitted key permit the bar to move inward from the barrel slot to permit cylinder rotation and thereby eifect unlocking and which upon withdrawal of the key causes the bar to move outward into the barrel slot to prevent cylinder rotation and thereby efiect locking, the said spring tumblers when the locking means is in unlocking position serving by reason of their engagement with the key to resist key withdrawal, a movable member carried by the cylinder and so located that it can enter the recess in the barrel wall when the cylinder is in looking position, the said member upon rotation of the cylinder being movable inwardly out of the barrel recess by the inclined sides thereof to an inner position in which it is adapted to enter a notch in the key to prevent key withdrawal and to thereby avoid strains upon the spring tumblers due to attempted withdrawal of the key, and a spring which biases the said movable member for outward movement into the barrel recess and out of the key notch so as to permit key withdrawal when the cylinder is in looking position, the said spring in conjunction with the said movable member and the said barrel recess serving to indicate to the user that the cylinder has been turned to locking position and also serving to resist turning of the cylinder out of locking position.

GUNNAR E. SWANSON.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 180,255 Miller July 25, 1876 347,445 Sherman Aug. 1'7, 1886 1,965,889 Fitz Gerald July 10, 1934 

